The present invention relates to belt associated power transmission apparatus and more particularly to an improved power transmission sheave of the grooved rim type to be associated with anyone of several preselected types of sheaves and drive belts and a method of manufacturing such an improved sheave.
Various types of grooved metal sheaves of cast iron, die cast and formed steel are known in the power transmission art, these different sheave types having different properties for different power transmission functions, each sheave type having a specific type of belt to be associated therewith in a power transmission assembly. Among the several differing properties of the varying sheave types are the material used, the hub and bushing type, the sheave diameter size, the angle of slope of the grooved side walls, the top and bottom widths of the groove and the groove depth. These properties have been important factors in arriving at the different and numerous commercial sheave types, including such well known single groove sheaves commonly known in the power transmission industry as the "A", the "B", the "5V", the "4L" and the "5L" sheaves, each of which is associated with an endless power transmission belt of a specific type. As will be discussed more fully hereinafter, these several sheave types, as well as the specific endless belts associated therewith, differ from each other in their above discussed physical properties. Although several organizations have established a certain uniformity in the angle of groove wall slope, such as the 36.degree. angle of groove wall slope adopted by the Society of Automotive Engineers (SAE) and the Goodyear Tire and Rubber Company range of 36.degree. to 42.degree. angle of groove wall slope, it generally has been the common practice to use a specifically designed sheave and endless drive belt for association with each sheave type and to insure that both drive and driven sheaves are of a compatible similar type. It also has been generally recognized that departure from such practice in the past could lead to undesirable problems in power transmission efficiencies and to power losses, poor belt performance, poor belt body and belt cord wear and undesirable belt-groove bottoming with some of the associated undesirable problems aforediscussed concomitant with such undesirable belt bottoming.
The present invention, recognizing the past undesirable problems associated with proper sheave and belt selection from the many types of belts and sheaves commercially available and also recognizing the undesirable problems associated with the comparatively extensive stocking and possible improper belt and sheave matching, provides a unique and novel sheave structure and method of manufacture which greatly simplifies sheave stocking and selection, assuring commonality and compatibility of usage in place of or with any one of the several above recited types of sheaves and associated belts therefore over a broad horsepower range without incurring the above discussed undesirable problems which could arise through possible mismatch. In addition, the present invention provides a unique sheave which allows for greatly increased belt life without belt bottoming and with increased heat dissipation between belt and sheave. Moreover, the present invention recognizes and resolves a need for providing a single type of sheave which includes recognized critical properties of increased top groove width and increased groove depth, a preselected angle of groove side wall slope and groove bottom width, which properties satisfy usage with belts and sheaves of varying preselected types, each of which types is generally well known for use in the power transmission arts in a comparatively more restricted environment.
Various other features of the present invention will become obvious to one skilled in the art upon reading the disclosure set forth herein.